The invention relates to a machine for applying pellets and powder to the soil incorporating, first, a reservoir with outlets, second, ridge wheels that are rotated by a drive shaft at varying rates and that distribute uniform volumes of the material flowing out of the reservoir through the outlets into exit pipes that communicate with a blower and that have outflow openings, and, third, base plates below the ridge wheels.
A machine of this type is known from German Auslegeschrift No. 2 924 625. One particular advantage of such a machine is that it can apply either large volumes of any type of commercial fertilizer per unit of area or extremely small volumes of either micropellets or fertilizer with a high percentage of nitrogen or parasite-control and weed-control agents per unit of area. When micropellets are applied, the machine's conventional ridge wheels are replaced with wheels that have a denser pattern or ridges.
There is, however, one disadvantage to this type of machine. The intervals or depressions between the individual ridges on the ridge wheels can get clogged up, especially when a damp material is being applied, which makes it impossible to distribute the material uniformly. Less and less material gets applied as the intervals get more and more clogged up. If the situation continues, no material at all may get applied.
A device for distributing uniform quantities of pellets or powder is known from German Pat. No. 2 208 834. The advantage of this device is that it incorporates means for cleaning out the intervals between the ridges. It also has a drawback, however. Since the depressions between the ridges, which are positioned one after the other in the sense of rotation do not get scraped out, damp material can also get distributed unevenly from this type of machine.
Still another type of machine for applying pellets and powder, especially micropellets, is known from the Evrard DM 12 prospectus. One advantage of this machine is that it has brushes for cleaning the ridge wheels. The drawback to this type of machine is that the brushes themselves get clogged up, especially when the material being applied is damp. The separate bristles on the brushes tend to stick together, so that, instead of cleaning the ridge wheels, the brushes actually accelerate the clogging up of the intervals between the ridges.